Cocaine is a powerful euphoriant and it relieves, though only transiently, depression, dread and dysphoria. New patterns of cocaine abuse, such as the inhalation of vaporized cocaine base, the intravenous injection of cocaine hydrochloride and the smoking of coca paste, produce a brief elation that quickly gives way either to a return to the baseline mood or to displeasure, resulting in a strong desire to return to the momentary ecstatic experience, a cycle that leads to compulsive use.

The enormous profits made from illicit traffic in cocaine lead to corruption, violence and political destabilization. The individual costs of cocaine abuse include loss of personal fortunes, jobs and families. The safety of cocaine use is a myth. There are a number of ways in which cocaine can be lethal. The high doses of cocaine abused today induce physical dependence, but this is less a contributory factor than the intense psychological craving to perpetuate cocaine use. There is no specific way to treat dysfunctional cocaine use; instead the treatment plan must deal with the individual's specific situation. Except for a reduction of cocaine supply at the source, preventive measures are only feasible in the context of abstinence from all abusable drugs.

The first cycle of cocaine abuse came to an end a century ago. By 1859 Albert Niemann of Gttingen had isolated and named cocaine, the principal alkaloid in coca leaves. During the next quarter of a century, a number of physicians and laymen became intrigued with the potential of this new and powerful stimulant of the central nervous system. According to the patent medicine testimonials of the day, it was a cure for all the ailments of mankind, and physicians prescribed it for alcoholism, depression, morphinism, tuberculosis, impotence and a wide variety of other maladies.

The claims made for this panacea are easy to understand. By elevating the mood, increasing alertness and diminishing fatigue, cocaine provided symptomatic relief for many chronic illnesses and for the depressions that often accompanied long-standing disability. It was only when overdoses, paranoid psychoses and the inability to stop persistent cocaine use were encountered that the enthusiasm for the drug turned to disillusionment, and its abuse receded, but never quite ceased.

Having such properties, it is almost inevitable that cocaine should enjoy periodic upsurges in use. During periods of social turbulence, when drugs are readily available, potent euphoriants are in demand. As their adverse consequences become recognized and legal controls are imposed the use of these substances recedes. When the complications of prolonged compulsive use are forgotten, a drug like cocaine is rediscovered.

Cocaine is absorbed through all the mucous membranes. Absorption through the nasal mucous is preferred to oral administration because this method avoids a first-pass metabolic breakdown in the liver. Vaginal, rectal and other mucosal routes have also been employed. Complications of cocaine sniffing include rhinitis, sometimes ethmoiditis, mucosal erosions and infrequently, perforation of the cartilagenous nasal septum.

Intravenous use is effective within 15 - 20 seconds
[
1] . Subcutaneous and intramuscular injections were used for the first few years after the drug was introduced, but are not being reported at present.

Inhalation of the vapours of alkaloidal cocaine, known as "basing" or "freebasing", has become a popular practice because of the rapidity of onset and the intensity of the euphoric experience. The reason for converting cocaine hydrochloride, the salt sold in licit and illicit commerce, to basic or alkaloidal cocaine is that the latter substance volatilizes at a temperature of about 98°C while the salt volatilizes at about 195°C a temperature which decomposes some of the cocaine hydrochloride
[
2] . Since the substance is absorbed by pulmonary capillaries, and moves from the lungs to the left side of the heart and then directly to the brain, the effects are perceptible in 7 - 10 seconds.

Cocaine consumption is often part of a multiple drug-abuse pattern. The "speedball", a combination of intravenous injections of cocaine and heroin is not new, but its use is increasing. It apparently decreases the tense, irritable, overactive symptoms that some people notice with cocaine alone. Abusers may also use heroin to come down from the stimulating effects of cocaine. Other depressants of the central nervous system, such as alcohol, methaqualone, barbiturates and benzodiazepines, may also be used for the same purpose or to procure sleep. In these cases, in addition to the problem of cocaine abuse, a physical dependence on depressant drugs may develop and require treatment.

Coca paste is a related preparation that is smoked, mixed with tobacco or cannabis, in a number of South American and Caribbean countries. Coca paste is the white or tan first-extraction product of the coca leaves. It consists of 40 -91 per cent of cocaine as the sulfate or alkaloid, plus a number of the other alkaloids present in the leaves
[
3] . Unlike alkaloidal cocaine (freebase), coca paste is relatively inexpensive and is widely abused by low-income populations. Its effects and side effects are similar to those of freebase.

The abuse of cocaine should be carefully distinguished from the practice of chewing coca leaves or drinking coca tea. The slow and incomplete extraction of the latter products, and efficient hepatic metabolism, make oral intake only mildly stimulating and their use is not to be compared with the more rapid and efficient delivery systems provided through intravenous injection, the inhalation of cocaine alkaloid or the smoking of coca paste.

The resurgence of cocaine use in the past decade was accompanied by two popular beliefs that enhanced its acceptability. One was that it was a status symbol, a drug used by jet-setters, affluent and sophisticated people. By weight it does not cost more than heroin. A few days of cocaine use can, however, consume hundreds or thousands of dollars' worth of the material. Therefore, compulsive use requires large amounts of money or access to huge quantities of cocaine.

The second belief was that cocaine was safe, and had few or no adverse effects. This notion may have arisen because the first cocaine users in the recent epidemics were only infrequently sniffing the drug. Now that compulsive sniffing, smoking and intravenous patterns are more frequent and larger doses of cocaine are being taken, many serious and lethal consequences of cocaine dependence are being seen.

Although the coca bush can be grown in many areas of the world, the important growing areas are in Bolivia, Colombia and Peru. According to estimates, Bolivia and Peru each probably produces about 50,000 tonnes of leaves a year. About 25 percent of the harvest is likely to be consumed by the indigenous population, who chew the coca leaves. Another 2 per cent is exported in legitimate commerce to flavour cola drinks and manufacture pharmaceutical cocaine. About 75,000 tonnes of leaf might remain available for the production of illicit substances. To this amount must be added an increasing production of coca leaf in Colombia. On the basis of such estimates, some 85,000 tonnes could well be available for coca paste and cocaine.

The major processing and trans-shipment operations are in Colombia. Cocaine is moved by ship and plane to distribution points in the Caribbean, Europe and South-east Asia
[
4] . Coca paste is usually produced on the spot in the growing areas and moved relatively short distances, by rail or motor vehicle, to nearby cities or across national boundaries.

If 85,000 tonnes of coca leaves are available for illegal purposes, 420 tonnes of coca paste can be made from it each year. The quantity actually sold as coca paste is unknown. Assuming that approximately 10 tonnes of paste undergoes no further processing, about 160 tonnes of illicit cocaine hydrochloride might be available for the world market, because it takes about 2.5 tonnes of the paste to make 1 tonne of cocaine. If approximately 15 per cent is lost to illicit commerce by interdiction in the land of origin and the receiving country, then cocaine supplies on the black market may exceed 130 tonnes. This amount is much more than the estimated current illicit demand for cocaine, which may be some 80 tonnes a year throughout the world. Some of the remaining 50 tonnes is being stockpiled, some is being used to develop new markets, and established markets are being over-supplied. As a result illicit cocaine supply is increasing in purity. A few years ago, the cocaine that was seized usually had a 12 per cent purity content. It is now from two to four times as strong. In addition, the street price has dropped from $US 100
-150 a gram to $US 75 - 100 a gram. These developments - increased potency and decreasing prices - are ominous. They mean more dependency on the drug and the opening of entirely new markets to less affluent people who could not afford to sustain a cocaine habit in the past.

It is difficult to conceptualize the amount of money involved in the cocaine traffic. It is also misleading, because quantity, more than quality, determines profits. If 1 tonne of coca leaves cost $US 2,000, the amount of coca paste that can be made from it will be 5 kg costing $US 10,000. From that quantity of paste, 2 kg of cocaine hydrochloride can be produced, which would Sell for $US 40,000 in Colombia or for $US 120,000 in New York City. Cutting the purity of cocaine for retail sale, the 2 kg would become 8 kg, and would be worth $US 480,000. Further cuts would increase the price, as would selling it in ounce or gram quantities. For example, if cocaine sells for $US 100 a gram, then the 8 kg will sell for $US 800,000. In 1980, the estimated intake from the sale of cocaine in the United States of America alone was more than 30 billion dollars, all tax free.

In view of the billions of dollars that pass through the hands of unscrupulous men, it is not surprising that a portion of the money is used to bribe and corrupt lawyers, doctors, bankers, judges and politicians. The cocaine industry can destabilize Governments and can disrupt whole economies in the countries involved. Murder is an increasing hazard to those involved in such illegal industry. Meanwhile, the cocaine syndicates use part of their proceeds to underwrite other illegal income-generating activities.

On a personal level, the tragedy becomes visible rather than clandestine. Large personal fortunes have been spent on cocaine. An expenditure of $US 1,000 a week on cocaine is not unusual. Homes and jobs have been lost and families disrupted as a result of cocaine abuse.

While strenuous efforts have been made to eradicate the coca plantations and destroy the cocaine factories, corruption makes these efforts only marginally successful. Furthermore, the farmer subsisting on coca cultivation has no concept of the impact of cocaine dependence upon some distant individual. Pressures to bring the cocaine traffic under control are, however, increasing. Thousands of Peruvians, Bolivians and Colombians have become psychotic or otherwise impaired as a result of smoking coca paste, and government leaders are becoming aware of the adverse impact of the drug upon the health and economic welfare of their countries.

It will be years before a significant blow can be dealt to the cocaine agrobusiness in the countries where coca is grown. The present form of eradication, by pulling up the bushes by hand, cannot begin to solve the problem. Aerial spraying with a herbicide now being used on foodcrops is a feasible alternative. It is imperative that alternative preventive efforts be made. Attempts should be made to reduce demand through primary and secondary preventive methods. One educational measure would be to disabuse those at risk of the idea that cocaine is a safe drug. A number of users have been seen to turn away from cocaine because they have observed the extremely adverse effects of cocaine use on their friends.

A few people are hypersensitive to even small amounts of cocaine. When used as a local anaesthetic or as a euphoriant, as little as 20 mg can be fatal, although the lethal dose for 50 per cent of the population is estimated at 1,200 mg taken intravenously. The basis for hypersensitivity is a congenital deficiency in the ability of the blood and liver esterases to metabolize cocaine. The reported numbers of cocaine deaths are underestimated because, after death, plasma cholinesterase continues to degrade cocaine, so that it may not be discovered by an autopsy.

Sudden death can also occur in cocaine users suffering from coronary artery disease. Patients with a history of angina have been found dead with white powder still in their nostrils. The increased demand of the heart for oxygen following cocaine-taking causes coronary insufficiency. The increased heart rate, blood pressure and general excitation is too much for an already embarrassed coronary circulation. Cocaine may also constrict coronary vasculature.

Body packing, a way of smuggling small quantities across national borders, consists in swallowing rubber sheaths containing cocaine before passing through customs. Occasionally these break, perhaps as a result of peristaltic action. The absorption of large amounts of the drug can cause death before a medical facility is reached.

Ventricular fibrillation or respiratory arrest are the modes of death in instance of overdose from intravenous, smoked or inhaled cocaine. When the purity of cocaine on the black market increases, overdose reactions increase too. It is possible to take a lethal dose by inhaling cocaine
[
6] .

Acute increase in blood pressure following cocaine use can rupture a weakened cerebral blood vessel, causing haemorrhage and disability or death.

When cocaine is injected, any of the diseases caused by unsterile needles can be contracted. Hepatitis and infections of the bloodstream have been reported. Recently, a small number of people who used cocaine intravenously developed the auto-immune deficiency syndrome (AIDS).

The system regulating the body temperature is disturbed by cocaine use. Vaso-constriction can prevent heat loss, over-activity will increase heat production, and a direct effect on the heat regulatory mechanism can cause hyperthermia.

The illicit cocaine trade is a high-risk enterprise, in which violence is a frequent occurrence.

Post-cocaine depression is intense and can lead to suicide. The depression is apparently due to a depletion of dopamine and an insensitivity of dopamine receptors after a cocaine "run". In addition, the guilt feelings that may emerge after the return to sober reality intensify the suicidal potential.

The paranoid thoughts that almost invariably develop among consistent cocaine users lead to miscalculations of the environment. Excessive suspiciousness can lead to bystanders being hurt. Accidental deaths during cocaine intoxication are likely because of the delusions, impaired judgement and impulsive decision-making to which it gives rise.

The long-term effects of smoking coca paste and cocaine base are unknown. In measurements of pulmonary function during non-using intervals, smokers were found to have an impaired ability to transfer oxygencarbon-dioxide across the pulmonary alveoli
[
7] .

In the older professional literature it was stated that cocaine did not produce physical dependence. In fact, that statement was correct because the quantities of cocaine used were small compared with the amounts taken by drug users today. The high doses of cocaine currently used and the frequency with which it is taken produce tolerance and a withdrawal syndrome, the latter consisting of psychological depression, excessive eating and sleeping and bodily discomfort. Cocaine users find themselves impelled to return to cocaine because of the positive reinforcement (reward) of the intense euphoria, the negative reinforcement (punishment) of the intense dysphoria experienced after discontinuing its use, which is relieved by using more cocaine, and the inability to enjoy life's sober pleasures because the reward centres of the brain have been overstimulated and are temporarily refractory to normal stimuli. Except for the psychological depression, physical dependence is not a major factor in driving the cocaine user back to drugs.

It is not often that animal research can be directly applied to the human condition. Studies on the behaviour of non-human primates that have been given cocaine reveal a striking resemblance to the behaviour seen in chronic cocaine users. When access to the drug is unlimited, monkeys will administer cocaine to themselves by pressing a bar until they die of exhaustion or convulsions. If a large amount of the drug has been provided, the primates will continue to press the bar even when 12,800 responses are required to obtain a single dose. Monkeys prefer intravenous cocaine to intravenous amphetamines. They prefer the drug to food that is in the cage, even when they are starving
[
8] . Male monkeys will continue to press the bar even when a receptive female is available. They will press the bar that will yield a high dose but will give them an electric shock in preference to the bar that provides a low dose without administering a shock. Cocaine has the most reinforcing effect of any drug known.

While 80 per cent of the people who have tried cocaine never become compulsive users, health-care professionals are seeing more and more people in serious trouble because of their inability to control the use of this drug. Cocainists may have spent a fortune on the drug or have descended into a paranoid state that impairs their ability to function on the job or in social or marital settings. Some who request treatment suffer from physical debilitation due to the weight loss caused by loss of appetite, sleeplessness resulting from the hyperarousal, and the general neglect of hygiene that accompanies preoccupation with the cocaine career. The most serious medical problem during the withdrawal phase is a depression that can be suicidal. The emergency management of cocaine poisoning will not be discussed here. For a review of the subject see reference
[
9] .

Since cocaine has such a reinforcing effect, it is difficult to treat. The euphoric experience gained from cocaine use is far more rewarding than abstinent existence. Too many patients give up treatment and return to cocaine despite the realization that its abuse is destructive. One determination to be made in the treatment plan is whether outpatient or inpatient care is needed. In general, it is worth attempting a trial period of ambulatory care. Residential treatment is usually beneficial for patients with the following characteristics:

Dealers who have continuing ready access to cocaine supplies;

Wealthy compulsive cocaine users, especially those who come into contact with other cocaine users, for example, those in the entertainment industry;

Those who have a depression with suicidal tendencies;

Those who are so physically depleted that they will require medical rehabilitation;

Overtly psychotic cocaine users;

Cocaine-dependent persons who have repeatedly failed to respond to outpatient care.

If outpatient care is attempted, the therapist must be available for impending or actual emergencies. The patient should be seen frequently at the outset, then less often as abstinence continues.

It is essential to insist on complete abstinence from cocaine. Many therapists will request the right to obtain urine specimens at any time. Depending on the dosage, cocaine or its metabolite are positive in urine for 24 - 72 hours after the last use. A few therapists have agreed to try to help the patient reduce his intake in order to decrease the cost of the habit. This is not a viable therapeutic goal and in such cases a relapse into heavy cocaine use is predictable.

If, in addition to cocaine dependence, there is a concurrent dependence on another drug or drugs (for example opiates, alcohol or sedatives), such dependence must also be treated, so that the patient can become drug-free. Depressants of the central nervous system will need to be gradually discontinued.

Abrupt withdrawal from cocaine is recommended. A gradual detoxification is not necessary, since the major symptoms of abstinence, such as delirium and convulsions, do not occur, and patients may well be lost during the tapering-off period without their ever having really engaged in therapy.

After discontinuance, the emergence of a post-cocaine depression can be expected and may last for weeks. A course of the tricyclic antidepressants may be desirable. The substitution of an amphetamine or an amphetaminelike drug is not indicated.

The cocaine user who seeks treatment is well aware of the insidious, compelling and destructive nature of cocaine dependence. It is worth providing information about the many and serious consequences of continued cocaine abuse in order to reinforce the patient's motivation to abstain. Sufficient knowledge of the sequellae of chronic cocainism is at hand to make possible an honest presentation of the prospects of continued abuse. The paradox of cocaine use should be described. What started out as a search for euphoria inevitably ends as dysphoria and depression.

The family should be involved in the treatment for a number of reasons. Family members can provide additional information about the patient's drug use and its consequences. Not infrequently, they have been consciously supporting the patient's cocaine use by providing funds or by permitting its use, or have been unconsciously doing so by allowing the patient to borrow or steal money or saleable items from them. The members of the family need detailed instructions on how to deal with the cocaine-obsessed individual. They must set limits and not allow the patient to manipulate them. If an important underlying family problem is identified as contributing to the cocaine use, an effort should be made to solve the problem. The intact and stable family is a source of support for the recovered cocainist.

Individual counselling and reality-oriented therapy are helpful in clarifying what cocaine means to the patient, how he became over-involved, and what he must do to avoid relapse. An explicit agreement between patient and therapist is helpful, each of them accepting certain responsibilities. Many cocaine users have psychological difficulties that existed before they embarked on drug abuse. Cocaine abuse will have exacerbated the mental problems and has added many emotional and situational difficulties. All of them need attention and, if possible, resolution. If a group of cocaine dependent persons who are in the process of recovery can be brought together to share their problems and provide support, this can enhance the therapeutic effort.

Self-help groups modelled on Alcoholics Anonymous or Narcotics Anonymous provide assistance and support during or after the treatment phase. Recently, Cocaine Anonymous groups have been formed in cities where large numbers of users exist.

During treatment, certain crises may occur. These are usually the following:

The cocaine-dependent person may leave shortly after entering the programme because the distress of being without cocaine is too acute to bear, and the prospects of a drug-free existence seem hopeless. At this point, the patient may drop out or even attempt suicide;

After a few days or a week of abstinence, the patient may incorrectly assume that he or she is cured. Upon embarking on treatment, the patient should be warned that the notion that one is cured shortly after abstinence is an illusion. Instead, treatment and follow-up must be understood to be a long process. There can be a relapse after months or years of abstinence;

After a long period of abstinence, the former cocaine abuser may try the drug again on the assumption that he can now control it. This sort of rationalization can lead to a disastrous return to compulsive use.

At times, the prospect of achieving abstinence is so problematical that desperate measures may be indicated. Contingency contracting is such a measure. The therapist and patient agree that, if the patient relapses, his worst fears will be quickly realized. The patient writes and signs a letter of confession to his or her spouse or employer or to the police. The letter is retained by the therapist, but will be mailed if the patient suffers a relapse or has a positive urine result. The drastic nature of this measure shows how difficult it can be to give up cocaine. The group that uses the technique believes that it makes the punishment for using cocaine more immediate, and therefore more effective. Of 32 patients who signed such contracts, only one had a relapse during the three-month period of the contract. Those who refused to sign did poorly. Renewal of the contract upon termination should be encouraged
[
10] .

Although cocaine antagonists exist, cocaine users or ex-users will not take them. The antagonists include the phenothiazines and butyrophenones, which are dopamine blockers. There is a need for treatment of certain patients with antidepressant, anticonvulsant and antihypertensive drugs; for cocaine psychoses the neuroleptic drugs are indicated.

If cocaine has been the focal point of the user's existence for months or years, it is sometimes necessary to rebuild the individual's life-style. Jogging and running have been mentioned as possibly helpful activities. For those who have tried to use cocaine to improve their job performance or excel at sports, it is necessary to devise techniques that will instil confidence in their sober mental and physical resources.

Lithium has been recommended as an agent that reduces cocaine euphoria, but its use is still considered to be experimental. Tyrosine is used by a few therapists to restore dopamine levels in the brain. Although tyrosine is a dopamine precursor, the clinical results have not been sufficiently confirmed. Some chronic users will require nutritional therapy to restore protein, vitamin and mineral balance. Because of their neglected hygiene and poor food intake, users may have developed dental problems that will require attention. ln some intractable cases of cocaine-dependent persons who have failed to benefit from more conservative therapy, bilateral cingulotomies have been performed. Although gratifying results have been reported
[
11] , the procedure cannot be recommended. That psychosurgery should be considered and indeed performed shows how hopeless the situation can become.